A diversity antenna system of a mobile device may include antenna elements that receive signals from and transmit signals to a base station. Signal reception and transmission may be improved by steering the radiation pattern of the antenna elements. For diversity reception, the signal-to-noise ratio (SNR) of an incoming signal may be improved by directing the main lobe of the pattern towards the signal. For diversity transmission, the pattern may be directed toward the base station to improve transmission. An adjuster may be used to adjust a signal to steer the radiation pattern. Known techniques for adjusting signals, however, may be inefficient. Efficient adjustment of signals may be desired.